Piston for air-compressors.



No. 852,889. PATENTED 'MAY 7, 1907.

R. MIEHLB.

P-ISTON POR AR COMPRESSORS. APPLIOATION F'ILBD JULY24.1905.

srarns aranci errori..

ROBERT MIEIILE, or oHIoAco, ILLINoIs.

PlSTON FOR AER-COMPRESSQRS.

pumps, and more particularly to that type ofv piston depending upon a cup leatherH as Itspacking.

he Improvements are' addressed to the means for expanding the packing or cup leather, and the invention has for its 'object to provide a nieans for this purpose which shall be simule and efficient, and in which liberal provision is made fory ingress of the air to the cup leather around the edges of the ex ander.

lhe invention consists in the vfeatures of novelty by which these objects and certain other objects which will hereinafter appear are accomplished, all as fully described with reference to the accompanying drawings, and more particularly pointed out in the claims.

In the said'drawings,-Figure 1 is a longitudinal sectional view of a piston embodying this invention; Fig. 2 is a face -view thereof, looking from the right in Fig. 1 Fig. Sis a detail view of the strip or blank of which the s reader is composed; Fig.' 4 is an enlarged eta-il view of one end thereof; and Fig. 5 is a cross-section thereof, showing the tongues of the spreader bent to thei'rfinal form.

1 is the piston head, which may bero vided with a hub 2A for the attachment o the piston rod, not shown, or any other suitable connection, the head being--of the usual or any appropriate form, with a peripheral 'flange 3 near one end thereof, which constitutesa seat or shoulder against which is arranged the inner edgeof the aforesaid spreader 4. This spreaderis composed preferablyof. a single strip of sheet steel, or any ther suitable elastic substance-possessing the requisite strength, which is rovided throughout its entire length with ong and short tongues 5, (i, 7, extending transverselyv of the'strip, which is lapped around the head 1 with its edge against the flange or seat 3, as before mentioned. rlhese tongues 5', 6, 7, may be produced by slitting the strip trans.-

versely, and the strip being composed of steel" or elastic material the tngues will constitute" Specification of Letters Patent. Appiication filed July 24, 1 905. smal No. 270,917.

Patented May 7, 1907.

individual springs.,l The shortest of the'se tongues, which is shown at 6, have their oter ends bent outwardly at substantiallyright angles to their bodyportions to forni flanges or lugs 8, which engage with the outer' edge of a ring 9, composed of leather orany other suitable flexible material, arranged on the head 1 around the band 4 at a position between the flange 8 and these lugs 8 of the tongues 6,Where by the ring 9. will be held in place. 4These short tongues 6 inay be employed throughout' the length of the band 4 at suitable intervals apart, as may be required for retaining the ring 9 in place. In the exeinplication of the invention shown in the drawings they occur between everyalternate pair of the vtongues 5, which are longer than the tongues 6, and have their outer ends bent first inwardly as shown at 5, with respect to the center of the head 1, and then outwardly as shown at 5b, to produce beveled or inclined extremities againstwhich bears an expander 1l). rlhis expander is preferably in the forni of a ring having a beveled periphery or side 11 bearing against the inclined or beveled ends 5b of the tongues 5, and serving, when the expander is Inoved toward the tongues 5, to force the outer ends o'f the tongues outwardly in a lradial direction with respect to the head and thereby also crowding the band or ring 9 outwardly against the paking of the piston, which as before mentioned, is constituted by a cup leather 12 of the usual or any suitable form, arranged over and embracing 'the band 9, and having its ybottoni portion secured to the back of the head 1 in any suitable way, as

.by Ineans of a clamping ring 13, which is held being arranged inwardly with respect to the lip 15 of the cup leather and outwardly with respect to the edge of the ring 9 and the head 1, so as to leave a liberal passage around the expander for the ingress of the air to the cup leather, thereby avoiding the possibility of the space between the li-p of the cup leather and the' periphery of the expander becoming clogged with grease or dirt and rendering the device inoperative.

The longest of the tongues, 4or the tongues 7, which occur at suitable intervals throughoutA the length of the band 4, and preferably between. every alternate pair of the tongues 5, are bent inwardly at an 'angle to their body portions and radially with respect to the center of the head, but at an oblique angle to the Ifo axis of the head, as shown at 7, and serve as a bearing for the expander 10, and at the same time as a means for preventing the spreader constituted by the band 4 and its various tongues 5, from, by any possibili-ty, slippingout of its seat on the head. These angular bends 7 a of the longest tongues 7 also, by virtue of their elasticity, constitute a means of holding the expander 10 snugly against the nuts 16 of the bolts 14, and thereby not only preventing undue play of the expander, but producing sufficient pressure against the nuts to prevent them from working-loose. y

With a device thus constructed it will be seen that the inward movement ofthe expander locauses the spreader tongues 5 to move outwardly with a rotary direction of motion, taking for its center the oint of conjunction between the tongue and)the body of the band or strip 4, and by thus moving ontwardly they expand the leather or flexible ring 9 uniformly throughout its circumference, but at an angle to 'the axis of' the head, so that the cup leather l2 will be pushed outwardly with uniformity and with itsgreatest expansion at the edge or lip l5. It jwill also be seen that the spreader tongues 5, being turned inwardly by the bends 5*1l and thence outwardly by the bends 5b, and the surface of the expander being beveled where it engages with the corresponding beveled extremities 5b of the tongues, a great range of expansion is provided for. y

Hav-ing thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is:

1. In a device for the purpose described, the combination with a piston head, a packing embracing the same, and an expander movable toward the head, of spreaders interposed at intervals-between the head and f packing and comprising elastic spreading tongues, and means wherebyv the expander envages and spreads the sprcaders toward device for the vpurposev described,

the combination with a piston-head, a packing embracing the same,fand.an expander movable towardsaid head, of spreaders interposed between, the packing and head and having beveled or flaring ends engagedjl by the expander said spreaders comprising elastic tongues against which the expander engages.

4. In a device for the purpose described, the combination with a piston head, a packing embracing the same, and an expander movable toward said head, of a spreader for the packing interposed between the packing and the head and comprising elastic tongues against which the ex ander abuts, and elastic spreading tongues etween which the expander engages for expanding the packing.

5. In a device for the purpose described, the combination with a piston head, a packing embracing the. same and an expander movable toward the head, of an elastic band encircling the head under the acking and comprising outwardly exten ing elastic tongues, some of said tongues being bent inwardly and serving as` a bearingI for the expander, and others of said tongues being ari' ranged to partially 'embrace the expander,

whereby the inward movement'of the eX- pander will spread said lateral tonguesftoward the packmg. l

6. In adevice for the purpose described, the combination with a piston head, a packing embracing the same, and an expander movable toward said-head, of an elastic-band embracing the head underthe acking and comprising outwardly exten lng elastic tongues, which have their outer extremities bent first inwardly with respect to the center of the head, and tliencutwardly or ilared and engaging with the eriphery of the expander.

7. In a device or the urpose described, the combination with a piston head, and a packing engaging the same, of a beveled expander movable toward the head, a plurality of elastic spreader tongues arranged between the head and the acking'and having their outer extremities ilared outwardly and engaging against the bevel of said expander.

8. In a device for the purpose described, the combination with a piston head, a cup leatlr'r surrounding the head, a ring interposed etween the cup leather and the head, and an expander movable toward the head, of an elastic band embracing thehea'd under the said ring and comprising radially extending lugs engaging over the edgeof said ring IOO rre

for holding the ring in place, Vand lon'gi'tuiinally extending tongues between which said expander engages for forcing the ring otwardly against the cup leather,

In witness whereof, I have hereunto set my i Q. I-I. SEAM, FRANCIS A. IIoPxrNs. 

